1. Field of the invention
The present invention relates to a curable silicone resin composition comprising a component with a polycyclic hydrocarbon skeleton, which is useful as a material for optical devices or parts, insulation material for electronic devices or parts, or coating material.
2. Description of the Prior Art
Conventionally, epoxy resins have normally been used as a material for optical devices or parts, in particular, sealing material for light emitting diode (LED) elements. In the case of silicone resins, tests have been conducted relating to their use as molded members for LED elements (see patent reference 1 and patent reference 2), or their use as color filter materials (see patent reference 3), although actual applications are few.
In recent years, with white LEDs attracting considerable attention, factors which until now have been considered unimportant, such as the yellowing of epoxy resin-based sealing materials caused by ultraviolet light or the like, and the appearance of cracks and the like caused by the increases in heating value accompanying miniaturization, now require urgent solutions. The use of cured products of silicone resins with a large quantity of phenyl groups within the molecules has been investigated as one potential solution to these problems. However, future LED light sources are likely to follow the trend towards the use of devices that generate light of shorter wavelengths, and because both epoxy resin-based sealing materials and phenyl group-containing silicone resin sealing materials display poor light transmittance in shorter wavelength regions, their application to such LEDs that generate light in the shorter wavelength regions has proven problematic.
Furthermore, optical material compositions comprising, as essential components, an organic compound with at least 2 carbon-carbon double bonds within each molecule, and a silicon compound with at least 2 hydrogen atoms bonded to silicon atoms within each molecule, have also been proposed (see patent reference 4 to patent reference 8). However, problems arise when these compositions undergo heat curing to generate a cured product, including foaming, curing shrinkage, and coloring of the cured product.
[Patent Reference 1]JP10-228249A[Patent Reference 2]JP10-242513A[Patent Reference 3]JP2000-123981A[Patent Reference 4]JP2002-324920A[Patent Reference 5]JP2002-327114A[Patent Reference 6]JP2002-327126A[Patent Reference 7]JP2002-338833A[Patent Reference 8]JP2002-341101A